Breaker bar for gummed paper and the like



Sept, 15, 1931. F. MAYO ET AL BREAKER BAR FOR GUMMEJD PAPER AND THE LIKE Filed Sept. 19, 1929 ill! Patented Sept. 15, 1931 NITED STAT-es FRANK MAYO AND FRAENK L. FRAIZER,'OF TROY, OHIO BREAKER BARFOR GUMMED' PAPER AND THE LTKE Application filed September 19, 1929. Serial No. 393,818.

per to curl-or warp. It is common practice to draw the coated stock-under tension when dry over a comparatively sharp edged breaker bar, causing the direction of travel of the stock to abruptly change as it passes the bar. Usually the breaker bars are arranged in pairs in reverse diagonal relation acrossthe path of travel of thepaper. Asthe coated.

stock passes about thejbreaker bar, the surface coating is progressively broken intoa close succession of fine, hair-like, surface cracks. The reverse diagonal relation of the bars causes such cracks to be producedin in-] 7 I and unlikelyjto get out of repair. p

A- further object of the invention is to pro- 75 tersecting relation.

i For eflicient operation it is necessary that the bearing edges .of the breaker bars be maintained comparatively sharp or acute,

without, however, possessing a cutting edge. It is the present practice to, grindsuch bars to a substantially right angle or to somewhat less than a right angle to afford the required bearingor breaking edge. The constant fric tion of the traveling stock soon Wears such edge round thus materially thickening or,

fix

Widening the bearing surface, thus greatly impairing the efficiency of the bar and necesl :VldG areplaceable bearlng or Wear strip wh ch may be quickly and readily intersitating frequent regrinding. The breaker. bars being rather long, accurate grinding is a tedious and expensive operation and more or less diflioulty is experienced in securing a uniform bearingedge. Moreover, there is a tendency of the edgeof the bar to wear to greater extent at some points than at others, due not only to variation in the density or hardness of the material but also to variations of the tension of the stock and the thickness of scribed'and set forth in the claims.

the coating l p v V V The. present invention does not pertain to any new method ofoperation nor-to a 'ma-.

chine for carrying'out the process of breaking, but is confinedtothe breaker bar per se. it consists in providing the Working edge of the breaker bar with a replaceable, hardened insert or Wear strip.- This Wear stripis of uniform thickness throughout, the thickness of the Wear strip being equivalent to that of the most ehicient and desirable thickness of the working edge. The thickness of such edge is not increased by Wear, as is the case with the ordinarysolid or one piece bar. The 0 inserted wear strip may be a 'thin, fiatstrip of hardened material, clock-spring material having been successfully employed, or it may be a length of piano Wire of the requisite giameter seated in the angle of the breaker 5 The object of the invention is to simplify the structure as well as the meansand mode of operation. of breaker bars for coated fiexible materials, whereby they will not only be cheap in construction, but will be uni-r form in operation, of increased durability necessitating minimum maintenance'expense skilled mechanics. V 1

With the above primary and other incidental objects in View, as Will more fully appear in thespecification, the inventionconsists of the features of construction, the partsiand combinations thereof and the mode of oper-'v ation or their equivalents ,as hereinafter dechan ed without the employment,of highly 1 Referringfto the accompanying drawings 1 wherein s shown the. preferred, but obviously not necessarily the only, form of embodi a length of piano wire a reinforcement strip.

F ig. 4 is a similar View of a further modi ficatlon.

Fig. l 'is an enlargedsectional view of the arrangement illustrated'in Fig. 4;

Figs. 5 and 6' are diagrammatic-views illustrating comparatively the effectof wear upon th'epresent form of breaker bar and that upon the breaker bars as, heretofore constructed. Like parts are indicated by similarcharacters of reference through the'several views.

While the breaker bar herein described is especially designed for the treatment" of gu-mmed paper to effect a succession of surfacecracks in the dried gummed coating,

thereby reducing or'eliminati-ng the tendency ofthe paper to'curl and warp, it is =30 be understood that the 1nvent1on 1s also appllcaable to sheet material other than paperand' also to paper and' othersheetmaterials coat.-

. ed'with substances other than adhesive gum. -Furthermore the present breaker bar may 'be' embodied in various machines or apparatus for performing its function.

Referring to the accompanying drawings, Fig. 1 illustrates in simplified-form the meth- 0d of operation or treatment to which the gummed material'is subjected. Such material is ordinarily treated in rollform or in a continuous strip. which is advanced under tension by sultable power drlving means.

The previously gummed. and dried material is supplied from a roll '1 from which it passes about a breaker bar 2 arranged in diagonal relation to the path of travel. In passing about this breaker bar 2, the course of'the paper web. is changedtoone atapproximately a right angle, the web passing thence over spaced guide rollers 33'from the second of which the web is carried about a second breaker bar 2' also. arranged in diagonal re-f lationwith the path of travel of the paper web but inclined thereto reversely of the inclined relation of the firstbreaker bar. Again the direction of travel of the web is changed at a right angle asit passes about thebreaker bar, andthe treated material is received on the roll 4. In itstravel about the breaker bars 22,' the paper web is bent rather abruptly; The bendin the material thus ef- 7 fected travels progressively the entire length of the paper subjecting all parts of the coat ing to the same progressively advancing line of stress causing the coating to be flexed and broken. Under such progressive treatment,

all parts of the coated surface are subjected breaker bars arranged in reverse obli ue re lation to the path of travel, the lines of reakage are effected first in one direction andthen in a transverse direction thus thoroughly flexing the coatedmaterial, leaving it limp and flat.

Ordinarily the breaker bars heretofore em.- ployed have been either of substantially rectangular cross-sectional form affording av comparatively sharp right angle about which the coated material is; drawn or they have been formed with intersecting bevels affording a t -shaped margin or edge engaging the traveling coated material. In either case, as the bearing edge of the breaker bar wears d eto frictionlof the traveling web ofcoated material, it becomes more and more rounded, afi'ordingabearing surfaceof gradually in creasing width and consequently the coated Jeb is less abruptly turned] or deflected thereabout; e As the bearing edge widens through use, the efficiency of the bar is materially decreased and the material is not so thoroughly anduniforml-y flexed or broken. Moreover thisichange occurs progressively so that while the bar maybe efi'ective at the beginning of a run of coated material, its efficiency will decrease and the resulting product willnot be uniform. Frequent regrinding of such breaker bars has been found necessary.

To overcome these difficulties, the present breaker'bar preferably, though not necessarily, consists of two beveled, plates 55: arranged face to face, affording substantially the typical V-edge breaker baras heretofore employed. However, intermediate these plates 5+5 there'is interposed a stripof thin hard material as shown at 6. This material 6 forms abearing strip projectinga short distance beyond the-plates 5'-'5between which the strip Sis clamped. In practice, a strip of clock-sprim steel has been very successfully employed, such strip being approximately seventeen .th'ousan dths of'an inch in thickness.

Such strip may be of any suitable or desired.

width. Notionly is such material extremely hard and able to resist wear but being a flat strip of uniform thickness, the wearing away of the edge of the strip does not increase the area of the bearing surface as does the usual V-sha'ped orangle bani Thisis best illustrated in Figs 5 and 6.. Fig.5illustrates the nsaaceo contour of a typical V-shaped bar as heretofore employed, showing by spaced lines 7 successive stages of distortion and broadening of the bearing edge by wear. Fig. 6 is a simllar view of the present breaker bar illustrating by like spaced lines 7 that'under like degrees of wear the area and shape of the bearing surface remains unchanged.

Not only does the use of the wear strip 6 in the angle of the breaker bar insure uniformity of the product, but it materially increases the life of thebar and entirely eliminates the necessity for frequent regrinding.

lVhen the inserted wear strip 6 has been worn down into proximate relation with the angle of the bar, the clamp screws 8 which hold together the beveled plates 5 may be relieved and the wear strips 6 may be adjusted relative to the plates to project a more or less distance therebeyond. The insert or wear strip 6 is firmly and securely clamped at all times between the sections 5-5 of the breaker bar. Its material advantage, as before pointed out, lies in the fact that the shape and extent of the bearing edge is not changed or distorted by wear, it possesses increased resistance, provides a uniform bearing surface, and obviates the necessity for regrinding. V

In lieu of a fiat wear strip insertedin the angle of the breaker baras heretofore shown and described, such wear strip or insert may be round when of the required diameter.

For this purpose, a length of piano wire 9 may be employed. In Fig. 3 this piano wire insert 9 has been shown seated in the angle of a rectangular bar while in Fig. 4 the wire is seated in the angle of a 'V- shaped breaker bar. The angle of the bar in either instance is formed with a semi-cylindrical groove 10 to receive the hardened wire insert 9. Clamps 11 are provided for securing the wire 9 in its grooved seat. One of the clamps 11 is tghtened upon the wire while the wire is subjected to tension by means of a suitable tightening or tensioning device 12. Thereafter the second clamp 11 is tightened to grip and hold the tensioned wire in its seat. The piano wire being hard and wear-resistant will withstand a long period offoperation. The wear of the material upon the wire will not increase the bearing surface nor materiallychange its contour. The seat 10 in the angle of the bar is preferably, though not necessarily, slightly less in width than the diameter of the wire 9. That is to say, the grooved seat is slightly less than semi-cylindrical so that the bearing strip or wire 10 projects laterally slightly beyond such grooved seat. The

wire employed has a diameter substantially equivalent to the maximum thickness of the working edge of the breakerbar. When the wire shows signs of wear, the clamps 11 are relieved and the'wlre drawn along the bar2 to present a new section of wirein operative PbSltlOIh 3 Such new section is tensloned and clamped as before described.

. .Fro'mtheabove dGSCIlPtlOIlzlt'Wlll be ap parent that there is thus providedaidevice of the character described possessing the: particularifeatures of advantage before enumer ated as desirable, but which obviously is .sus-;

ceptible'ofimodification in itsform, proportions, detail construction and arrangement of parts without departing. from the prin-.

'ciple involved or sacrificing any of its ad vantages.

' VVh1le 1n order more orless specific as to structural features, it is to be understood that the invention is not limited to the specificdetails shown, but

thatthe means and construction herein, dis-l closed comprise the preferred form of several modes of putting the invention into efto comply with the statute the invention has been described in languagefeet and the invention is, therefore, claimed 7 in any; of its forms ormodifications within the legitimate and valid scope, of the append-' described our .i'n'ventiom;

coating upon coated flexible sheet material-,a

bar having angularly" disposed faces across which the materialis drawn, and a replace able lnsert of uniform thickness located at;

the intersectioniof said-jfac'es and forming a wean strip for the material.

2. As an article of manufacture, a breaking bar for breaking the dried coating upon coated flexible sheet material, an angular bar and ahardenedthin bearingstrip the maximum thickness of which is that of the desired breaker edge disposed at the angle of said bar to receive the material.

3. A breaker bar for breaking the dried coatlng upon coated flexible sheet material, including a hardened Wire, the diameter of which is substantially equal to the desired thickness of the breaking edge, an angular bar, a seat formed in the angle of the bar in which the hardened wire over which the material travels is removably mounted.

4. A breaker bar, for breaking the dried coating upon coated flexible sheet material including a thin flat strip of hardened material the acting edgeof which is the entire thickness of the strip, and a supporting bar upon which the strip is mounted with its margin projecting beyond the bar to receive the maextending therebeyond for engagement with the coated material.

6. In abreaker bar for breaking the dried coating uponaceate'd flexible material; a thin flair-strip of: hard materials about the margin of which the coated material -isdrawn'in reverse directionsythe strip havingasubstan- 5 tially uniform thickness equivalent to the maximumbearing surface for'the coated'material whereby the-wearingaway of the edge oflthe strip Will not; increase thexwidth' of the bearing; surface, and means for rigidly'supporting-the: strip: the thickness: of" Whicl'r is that ofthedesired'breaking ed'g' e'i" 7; As an article Jof manufacture, ab-reakerbar for breaking the dried coating of coated flexible material, a hardened Wire strip, the 2 acting edge-of WhiCh'iS of the entire thickness thereof,- and. aasupport: I therefor of angular cr0ss-sectional form and having a longitudinal recess therein coincident With one of it's1 angles,saidhardened Wire strips beingseatedin said recess for engagement with the coated material; and means for releasably liolding-saidstripin saidseat. I

8i As an article'of manufacture, a breaker bar for breaking the dried coating of coated 5- flexible material including a hardened wear strip; theacting' edge of which is theentire thickness thereof, and a support therefor in; 'which' the Wear! strip is adjustably mounted. i k 2 7 ee In testimony-where0fWe have'hereunto set I 1 our 'handslthis"16th -dayof September A.

"1929. v 4. Y FRANK MAYDz- FRANK LQERAIZERM 

